Ash, not sure about your area, but around here before you get to the arena you can go around it on outside, next to the box as well. May be just turn a horse as you pass the box and walk her back to pass it again in other direction.
P.S. I was very nervous too first time thinking my horse will spook or jump over the chains around the arena, but she did just fine. :) Just don't be nervous/afraid yourself when you enter the arena, and you'll be all right! Good luck!
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